isl_local_space.c

   1 /*
   2  * Copyright 2011      INRIA Saclay
   3  *
   4  * Use of this software is governed by the GNU LGPLv2.1 license
   5  *
   6  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
   7  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
   8  * 91893 Orsay, France
   9  */
  10
  11 #include <isl_ctx_private.h>
  12 #include <isl_map_private.h>
  13 #include <isl_local_space_private.h>
  14 #include <isl_dim_private.h>
  15 #include <isl_mat_private.h>
  16 #include <isl/seq.h>
  17
  18 isl_ctx *isl_local_space_get_ctx(__isl_keep isl_local_space *ls)
  19 {
  20         return ls ? ls->dim->ctx : NULL;
  21 }
  22
  23 __isl_give isl_local_space *isl_local_space_alloc_div(__isl_take isl_dim *dim,
  24         __isl_take isl_mat *div)
  25 {
  26         isl_ctx *ctx;
  27         isl_local_space *ls = NULL;
  28
  29         if (!dim)
  30                 goto error;
  31
  32         ctx = isl_dim_get_ctx(dim);
  33         ls = isl_calloc_type(ctx, struct isl_local_space);
  34         if (!ls)
  35                 goto error;
  36
  37         ls->ref = 1;
  38         ls->dim = dim;
  39         ls->div = div;
  40
  41         return ls;
  42 error:
  43         isl_dim_free(dim);
  44         isl_local_space_free(ls);
  45         return NULL;
  46 }
  47
  48 __isl_give isl_local_space *isl_local_space_alloc(__isl_take isl_dim *dim,
  49         unsigned n_div)
  50 {
  51         isl_ctx *ctx;
  52         isl_mat *div;
  53         unsigned total;
  54
  55         if (!dim)
  56                 return NULL;
  57
  58         total = isl_dim_total(dim);
  59
  60         ctx = isl_dim_get_ctx(dim);
  61         div = isl_mat_alloc(ctx, n_div, 1 + 1 + total + n_div);
  62         return isl_local_space_alloc_div(dim, div);
  63 }
  64
  65 __isl_give isl_local_space *isl_local_space_from_dim(__isl_take isl_dim *dim)
  66 {
  67         return isl_local_space_alloc(dim, 0);
  68 }
  69
  70 __isl_give isl_local_space *isl_local_space_copy(__isl_keep isl_local_space *ls)
  71 {
  72         if (!ls)
  73                 return NULL;
  74
  75         ls->ref++;
  76         return ls;
  77 }
  78
  79 __isl_give isl_local_space *isl_local_space_dup(__isl_keep isl_local_space *ls)
  80 {
  81         if (!ls)
  82                 return NULL;
  83
  84         return isl_local_space_alloc_div(isl_dim_copy(ls->dim),
  85                                          isl_mat_copy(ls->div));
  86
  87 }
  88
  89 __isl_give isl_local_space *isl_local_space_cow(__isl_take isl_local_space *ls)
  90 {
  91         if (!ls)
  92                 return NULL;
  93
  94         if (ls->ref == 1)
  95                 return ls;
  96         ls->ref--;
  97         return isl_local_space_dup(ls);
  98 }
  99
 100 void *isl_local_space_free(__isl_take isl_local_space *ls)
 101 {
 102         if (!ls)
 103                 return NULL;
 104
 105         if (--ls->ref > 0)
 106                 return NULL;
 107
 108         isl_dim_free(ls->dim);
 109         isl_mat_free(ls->div);
 110
 111         free(ls);
 112
 113         return NULL;
 114 }
 115
 116 /* Return true if the two local spaces are identical, with identical
 117  * expressions for the integer divisions.
 118  */
 119 int isl_local_space_is_equal(__isl_keep isl_local_space *ls1,
 120         __isl_keep isl_local_space *ls2)
 121 {
 122         int equal;
 123
 124         if (!ls1 || !ls2)
 125                 return -1;
 126
 127         equal = isl_dim_equal(ls1->dim, ls2->dim);
 128         if (equal < 0 || !equal)
 129                 return equal;
 130
 131         if (!isl_local_space_divs_known(ls1))
 132                 return 0;
 133         if (!isl_local_space_divs_known(ls2))
 134                 return 0;
 135
 136         return isl_mat_is_equal(ls1->div, ls2->div);
 137 }
 138
 139 int isl_local_space_dim(__isl_keep isl_local_space *ls,
 140         enum isl_dim_type type)
 141 {
 142         if (!ls)
 143                 return 0;
 144         if (type == isl_dim_div)
 145                 return ls->div->n_row;
 146         if (type == isl_dim_all)
 147                 return isl_dim_size(ls->dim, isl_dim_all) + ls->div->n_row;
 148         return isl_dim_size(ls->dim, type);
 149 }
 150
 151 unsigned isl_local_space_offset(__isl_keep isl_local_space *ls,
 152         enum isl_dim_type type)
 153 {
 154         isl_dim *dim;
 155
 156         if (!ls)
 157                 return 0;
 158
 159         dim = ls->dim;
 160         switch (type) {
 161         case isl_dim_cst:       return 0;
 162         case isl_dim_param:     return 1;
 163         case isl_dim_in:        return 1 + dim->nparam;
 164         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
 165         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
 166         default:                return 0;
 167         }
 168 }
 169
 170 const char *isl_local_space_get_dim_name(__isl_keep isl_local_space *ls,
 171         enum isl_dim_type type, unsigned pos)
 172 {
 173         return ls ? isl_dim_get_name(ls->dim, type, pos) : NULL;
 174 }
 175
 176 __isl_give isl_div *isl_local_space_get_div(__isl_keep isl_local_space *ls,
 177         int pos)
 178 {
 179         isl_basic_map *bmap;
 180
 181         if (!ls)
 182                 return NULL;
 183
 184         if (pos < 0 || pos >= ls->div->n_row)
 185                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 186                         "index out of bounds", return NULL);
 187
 188         if (isl_int_is_zero(ls->div->row[pos][0]))
 189                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 190                         "expression of div unknown", return NULL);
 191
 192         bmap = isl_basic_map_from_local_space(isl_local_space_copy(ls));
 193         return isl_basic_map_div(bmap, pos);
 194 }
 195
 196 __isl_give isl_dim *isl_local_space_get_dim(__isl_keep isl_local_space *ls)
 197 {
 198         if (!ls)
 199                 return NULL;
 200
 201         return isl_dim_copy(ls->dim);
 202 }
 203
 204 __isl_give isl_local_space *isl_local_space_set_dim_name(
 205         __isl_take isl_local_space *ls,
 206         enum isl_dim_type type, unsigned pos, const char *s)
 207 {
 208         ls = isl_local_space_cow(ls);
 209         if (!ls)
 210                 return NULL;
 211         ls->dim = isl_dim_set_name(ls->dim, type, pos, s);
 212         if (!ls->dim)
 213                 return isl_local_space_free(ls);
 214
 215         return ls;
 216 }
 217
 218 __isl_give isl_local_space *isl_local_space_reset_dim(
 219         __isl_take isl_local_space *ls, __isl_take isl_dim *dim)
 220 {
 221         ls = isl_local_space_cow(ls);
 222         if (!ls || !dim)
 223                 goto error;
 224
 225         isl_dim_free(ls->dim);
 226         ls->dim = dim;
 227
 228         return ls;
 229 error:
 230         isl_local_space_free(ls);
 231         isl_dim_free(dim);
 232         return NULL;
 233 }
 234
 235 /* Reorder the columns of the given div definitions according to the
 236  * given reordering.
 237  * The order of the divs themselves is assumed not to change.
 238  */
 239 static __isl_give isl_mat *reorder_divs(__isl_take isl_mat *div,
 240         __isl_take isl_reordering *r)
 241 {
 242         int i, j;
 243         isl_mat *mat;
 244         int extra;
 245
 246         if (!div || !r)
 247                 goto error;
 248
 249         extra = isl_dim_total(r->dim) + div->n_row - r->len;
 250         mat = isl_mat_alloc(div->ctx, div->n_row, div->n_col + extra);
 251         if (!mat)
 252                 goto error;
 253
 254         for (i = 0; i < div->n_row; ++i) {
 255                 isl_seq_cpy(mat->row[i], div->row[i], 2);
 256                 isl_seq_clr(mat->row[i] + 2, mat->n_col - 2);
 257                 for (j = 0; j < r->len; ++j)
 258                         isl_int_set(mat->row[i][2 + r->pos[j]],
 259                                     div->row[i][2 + j]);
 260         }
 261
 262         isl_reordering_free(r);
 263         isl_mat_free(div);
 264         return mat;
 265 error:
 266         isl_reordering_free(r);
 267         isl_mat_free(div);
 268         return NULL;
 269 }
 270
 271 /* Reorder the dimensions of "ls" according to the given reordering.
 272  * The reordering r is assumed to have been extended with the local
 273  * variables, leaving them in the same order.
 274  */
 275 __isl_give isl_local_space *isl_local_space_realign(
 276         __isl_take isl_local_space *ls, __isl_take isl_reordering *r)
 277 {
 278         ls = isl_local_space_cow(ls);
 279         if (!ls || !r)
 280                 goto error;
 281
 282         ls->div = reorder_divs(ls->div, isl_reordering_copy(r));
 283         if (!ls->div)
 284                 goto error;
 285
 286         ls = isl_local_space_reset_dim(ls, isl_dim_copy(r->dim));
 287
 288         isl_reordering_free(r);
 289         return ls;
 290 error:
 291         isl_local_space_free(ls);
 292         isl_reordering_free(r);
 293         return NULL;
 294 }
 295
 296 __isl_give isl_local_space *isl_local_space_add_div(
 297         __isl_take isl_local_space *ls, __isl_take isl_vec *div)
 298 {
 299         ls = isl_local_space_cow(ls);
 300         if (!ls || !div)
 301                 goto error;
 302
 303         if (ls->div->n_col != div->size)
 304                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 305                         "incompatible dimensions", goto error);
 306
 307         ls->div = isl_mat_add_zero_cols(ls->div, 1);
 308         ls->div = isl_mat_add_rows(ls->div, 1);
 309         if (!ls->div)
 310                 goto error;
 311
 312         isl_seq_cpy(ls->div->row[ls->div->n_row - 1], div->el, div->size);
 313         isl_int_set_si(ls->div->row[ls->div->n_row - 1][div->size], 0);
 314
 315         isl_vec_free(div);
 316         return ls;
 317 error:
 318         isl_local_space_free(ls);
 319         isl_vec_free(div);
 320         return NULL;
 321 }
 322
 323 __isl_give isl_local_space *isl_local_space_replace_divs(
 324         __isl_take isl_local_space *ls, __isl_take isl_mat *div)
 325 {
 326         ls = isl_local_space_cow(ls);
 327
 328         if (!ls || !div)
 329                 goto error;
 330
 331         isl_mat_free(ls->div);
 332         ls->div = div;
 333         return ls;
 334 error:
 335         isl_mat_free(div);
 336         isl_local_space_free(ls);
 337         return NULL;
 338 }
 339
 340 /* Copy row "s" of "src" to row "d" of "dst", applying the expansion
 341  * defined by "exp".
 342  */
 343 static void expand_row(__isl_keep isl_mat *dst, int d,
 344         __isl_keep isl_mat *src, int s, int *exp)
 345 {
 346         int i;
 347         unsigned c = src->n_col - src->n_row;
 348
 349         isl_seq_cpy(dst->row[d], src->row[s], c);
 350         isl_seq_clr(dst->row[d] + c, dst->n_col - c);
 351
 352         for (i = 0; i < s; ++i)
 353                 isl_int_set(dst->row[d][c + exp[i]], src->row[s][c + i]);
 354 }
 355
 356 /* Compare (known) divs.
 357  * Return non-zero if at least one of the two divs is unknown.
 358  */
 359 static int cmp_row(__isl_keep isl_mat *div, int i, int j)
 360 {
 361         int li, lj;
 362
 363         if (isl_int_is_zero(div->row[j][0]))
 364                 return -1;
 365         if (isl_int_is_zero(div->row[i][0]))
 366                 return 1;
 367
 368         li = isl_seq_last_non_zero(div->row[i], div->n_col);
 369         lj = isl_seq_last_non_zero(div->row[j], div->n_col);
 370
 371         if (li != lj)
 372                 return li - lj;
 373
 374         return isl_seq_cmp(div->row[i], div->row[j], div->n_col);
 375 }
 376
 377 /* Combine the two lists of divs into a single list.
 378  * For each row i in div1, exp1[i] is set to the position of the corresponding
 379  * row in the result.  Similarly for div2 and exp2.
 380  * This function guarantees
 381  *      exp1[i] >= i
 382  *      exp1[i+1] > exp1[i]
 383  * For optimal merging, the two input list should have been sorted.
 384  */
 385 __isl_give isl_mat *isl_merge_divs(__isl_keep isl_mat *div1,
 386         __isl_keep isl_mat *div2, int *exp1, int *exp2)
 387 {
 388         int i, j, k;
 389         isl_mat *div = NULL;
 390         unsigned d = div1->n_col - div1->n_row;
 391
 392         div = isl_mat_alloc(div1->ctx, 1 + div1->n_row + div2->n_row,
 393                                 d + div1->n_row + div2->n_row);
 394         if (!div)
 395                 return NULL;
 396
 397         for (i = 0, j = 0, k = 0; i < div1->n_row && j < div2->n_row; ++k) {
 398                 int cmp;
 399
 400                 expand_row(div, k, div1, i, exp1);
 401                 expand_row(div, k + 1, div2, j, exp2);
 402
 403                 cmp = cmp_row(div, k, k + 1);
 404                 if (cmp == 0) {
 405                         exp1[i++] = k;
 406                         exp2[j++] = k;
 407                 } else if (cmp < 0) {
 408                         exp1[i++] = k;
 409                 } else {
 410                         exp2[j++] = k;
 411                         isl_seq_cpy(div->row[k], div->row[k + 1], div->n_col);
 412                 }
 413         }
 414         for (; i < div1->n_row; ++i, ++k) {
 415                 expand_row(div, k, div1, i, exp1);
 416                 exp1[i] = k;
 417         }
 418         for (; j < div2->n_row; ++j, ++k) {
 419                 expand_row(div, k, div2, j, exp2);
 420                 exp2[j] = k;
 421         }
 422
 423         div->n_row = k;
 424         div->n_col = d + k;
 425
 426         return div;
 427 }
 428
 429 int isl_local_space_divs_known(__isl_keep isl_local_space *ls)
 430 {
 431         int i;
 432
 433         if (!ls)
 434                 return -1;
 435
 436         for (i = 0; i < ls->div->n_row; ++i)
 437                 if (isl_int_is_zero(ls->div->row[i][0]))
 438                         return 0;
 439
 440         return 1;
 441 }
 442
 443 /* Construct a local space for a map that has the given local
 444  * space as domain and that has a zero-dimensional range.
 445  */
 446 __isl_give isl_local_space *isl_local_space_from_domain(
 447         __isl_take isl_local_space *ls)
 448 {
 449         ls = isl_local_space_cow(ls);
 450         if (!ls)
 451                 return NULL;
 452         ls->dim = isl_dim_from_domain(ls->dim);
 453         if (!ls->dim)
 454                 return isl_local_space_free(ls);
 455         return ls;
 456 }
 457
 458 __isl_give isl_local_space *isl_local_space_add_dims(
 459         __isl_take isl_local_space *ls, enum isl_dim_type type, unsigned n)
 460 {
 461         int pos;
 462
 463         if (!ls)
 464                 return NULL;
 465         pos = isl_local_space_dim(ls, type);
 466         return isl_local_space_insert_dims(ls, type, pos, n);
 467 }
 468
 469 /* Remove common factor of non-constant terms and denominator.
 470  */
 471 static void normalize_div(__isl_keep isl_local_space *ls, int div)
 472 {
 473         isl_ctx *ctx = ls->div->ctx;
 474         unsigned total = ls->div->n_col - 2;
 475
 476         isl_seq_gcd(ls->div->row[div] + 2, total, &ctx->normalize_gcd);
 477         isl_int_gcd(ctx->normalize_gcd,
 478                     ctx->normalize_gcd, ls->div->row[div][0]);
 479         if (isl_int_is_one(ctx->normalize_gcd))
 480                 return;
 481
 482         isl_seq_scale_down(ls->div->row[div] + 2, ls->div->row[div] + 2,
 483                             ctx->normalize_gcd, total);
 484         isl_int_divexact(ls->div->row[div][0], ls->div->row[div][0],
 485                             ctx->normalize_gcd);
 486         isl_int_fdiv_q(ls->div->row[div][1], ls->div->row[div][1],
 487                             ctx->normalize_gcd);
 488 }
 489
 490 /* Exploit the equalities in "eq" to simplify the expressions of
 491  * the integer divisions in "ls".
 492  * The integer divisions in "ls" are assumed to appear as regular
 493  * dimensions in "eq".
 494  */
 495 __isl_give isl_local_space *isl_local_space_substitute_equalities(
 496         __isl_take isl_local_space *ls, __isl_take isl_basic_set *eq)
 497 {
 498         int i, j, k;
 499         unsigned total;
 500         unsigned n_div;
 501
 502         ls = isl_local_space_cow(ls);
 503         if (!ls || !eq)
 504                 goto error;
 505
 506         total = isl_dim_total(eq->dim);
 507         if (isl_local_space_dim(ls, isl_dim_all) != total)
 508                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 509                         "dimensions don't match", goto error);
 510         total++;
 511         n_div = eq->n_div;
 512         for (i = 0; i < eq->n_eq; ++i) {
 513                 j = isl_seq_last_non_zero(eq->eq[i], total + n_div);
 514                 if (j < 0 || j == 0 || j >= total)
 515                         continue;
 516
 517                 for (k = 0; k < ls->div->n_row; ++k) {
 518                         if (isl_int_is_zero(ls->div->row[k][1 + j]))
 519                                 continue;
 520                         isl_seq_elim(ls->div->row[k] + 1, eq->eq[i], j, total,
 521                                         &ls->div->row[k][0]);
 522                         normalize_div(ls, k);
 523                 }
 524         }
 525
 526         isl_basic_set_free(eq);
 527         return ls;
 528 error:
 529         isl_basic_set_free(eq);
 530         isl_local_space_free(ls);
 531         return NULL;
 532 }
 533
 534 int isl_local_space_is_named_or_nested(__isl_keep isl_local_space *ls,
 535         enum isl_dim_type type)
 536 {
 537         if (!ls)
 538                 return -1;
 539         return isl_dim_is_named_or_nested(ls->dim, type);
 540 }
 541
 542 __isl_give isl_local_space *isl_local_space_drop_dims(
 543         __isl_take isl_local_space *ls,
 544         enum isl_dim_type type, unsigned first, unsigned n)
 545 {
 546         isl_ctx *ctx;
 547
 548         if (!ls)
 549                 return NULL;
 550         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
 551                 return ls;
 552
 553         ctx = isl_local_space_get_ctx(ls);
 554         if (first + n > isl_local_space_dim(ls, type))
 555                 isl_die(ctx, isl_error_invalid, "range out of bounds",
 556                         return isl_local_space_free(ls));
 557
 558         ls = isl_local_space_cow(ls);
 559         if (!ls)
 560                 return NULL;
 561
 562         if (type == isl_dim_div) {
 563                 ls->div = isl_mat_drop_rows(ls->div, first, n);
 564         } else {
 565                 ls->dim = isl_dim_drop(ls->dim, type, first, n);
 566                 if (!ls->dim)
 567                         return isl_local_space_free(ls);
 568         }
 569
 570         first += 1 + isl_local_space_offset(ls, type);
 571         ls->div = isl_mat_drop_cols(ls->div, first, n);
 572         if (!ls->div)
 573                 return isl_local_space_free(ls);
 574
 575         return ls;
 576 }
 577
 578 __isl_give isl_local_space *isl_local_space_insert_dims(
 579         __isl_take isl_local_space *ls,
 580         enum isl_dim_type type, unsigned first, unsigned n)
 581 {
 582         isl_ctx *ctx;
 583
 584         if (!ls)
 585                 return NULL;
 586         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
 587                 return ls;
 588
 589         ctx = isl_local_space_get_ctx(ls);
 590         if (first > isl_local_space_dim(ls, type))
 591                 isl_die(ctx, isl_error_invalid, "position out of bounds",
 592                         return isl_local_space_free(ls));
 593
 594         ls = isl_local_space_cow(ls);
 595         if (!ls)
 596                 return NULL;
 597
 598         if (type == isl_dim_div) {
 599                 ls->div = isl_mat_insert_zero_rows(ls->div, first, n);
 600         } else {
 601                 ls->dim = isl_dim_insert(ls->dim, type, first, n);
 602                 if (!ls->dim)
 603                         return isl_local_space_free(ls);
 604         }
 605
 606         first += 1 + isl_local_space_offset(ls, type);
 607         ls->div = isl_mat_insert_zero_cols(ls->div, first, n);
 608         if (!ls->div)
 609                 return isl_local_space_free(ls);
 610
 611         return ls;
 612 }